1-chloropyrimidinyl-1H-1,2,4-triazole-3-sulphonamides as herbicides

ABSTRACT

The invention relates to new 1-chloropyrimidinyl-1H-1,2,4-triazol-3-sulphonamides of the general formual I ##STR1## in which A, R 1 , R 2 , R 3 , R 4  and R 5  have the meanings given in the description, processes for their preparation and their use as herbicides.

The invention relates to new 1-chloropyrimidinyl-1H-1,2,4-triazole-3-sulphonamides, processes for their preparation and their use as herbicides.

In EP Application 0 246 749 there are claimed herbicidal triazolesulphonamides of the formula: ##STR2## and salts thereof, where: R¹ represents hydrogen, a substituted or unsubstituted alkyl, alkenyl, alkynyl, cycloalkyl, aryl, aralkyl, acyl, alkoxycarbonyl, aminocarbonyl or sulphonyl, or a heterocyclic group;

R² represents hydrogen, halo, cyano, hydroxy, mercapto, a substituted or unsubstituted alkyl, alkenyl, alkynyl, alkoxy, alkylthio, alkylsulphinyl, alkylsulphonyl, acyl, alkoxycarbonyl, aminocarbonyl, aryl or amino group, or a heterocyclic group;

R³ represents a substituted or unsubstituted heterocyclic, benzheterocyclic, aryl or aralkyl group; and

R⁴ represents hydrogen, a substituted or unsubstituted alkyl, alkenyl, alkynyl, acyl, alkylsulphonyl, alkoxycarbonyl, aminocarbonyl, aralkyl, or a group of the formula: ##STR3## where R¹ and R² are as defined hereinbefore.

We have now found that a particular group of compounds within this broad claim have especially valuable properties. The selection of this group could not be predicted from the prior document nor could it be predicted that this group of compounds would show the particular advantages.

According to the invention there are provided 1-chloropyrimidinyl-1H-1,2,4-triazole-3-sulphonamides of the general formula I ##STR4## in which A is --S-- or --CH═CH--;

R¹ is halogen, methyl, trifluoromethyl, methoxy, difluoromethoxy, nitro or methoxycarbonyl;

R² is hydrogen, halogen, methyl, methoxy, allyloxy or propargyloxy;

R³ is hydrogen or methyl;

R⁴ is hydrogen, methyl or methoxymethyl; and

R⁵ is C₁ -C₄ -alkyl.

The compounds of the invention are thus 1H-1,2,4-triazole-3-sulphonamide derivatives, carrying a phenyl or thienyl group (with defined substituents) on the sulphonamide linkage and in which the triazole is substituted in the 1-position by a 4-chloro-6-(C₁ -C₄ -alkoxy)-pyrimidin-2-yl group and substituted in the 5-position by hydrogen, methyl or methoxymethyl. In EP Application 0 246 749 there are no examples of any compounds containing a 1-(4-chloro-6-(C₁ -C₄ -alkoxy)-pyrimidin-2-yl) group. Further the only example of a compound comprising a thienyl group on the sulphonamide linkage has no substituents on the 1-position of the triazole group and is substituted at the 5-position by a pyrrole group.

The compounds of the invention are characterised by good herbicidal activity and especially high activity against Matricaria spp., combined with good crop selectivity, particularly in sugar beet. This combination of good Matricaria activity (which is a particularly important and difficult weed to control in sugar beet) combined with good sugar beet selectivity, is not generally seen in the compounds disclosed in EP Application 0 246 749.

The compounds of the invention of general formula I can be prepared for example by

(A) reacting an amine of general formula II ##STR5## in which A, R¹, R² and R³ have the meanings given above, with a sulphonylchloride of general formula III ##STR6## in which R⁴ and R⁵ have the meanings given above, in a suitable solvent and in the presence of an acid acceptor, or

(B) reacting a compound of general formula IV ##STR7## in which A, R¹, R², R³ and R⁴ have the meanings given above, with a compound of general formula V ##STR8## where Z is chlorine, bromine or an alkyl- or arylsulphonyl group and R⁵ has the meaning given above, in a suitable solvent in the presence of an acid-binding agent.

The reaction variants are preferably carried out in the presence of a diluent. For this purpose there can be used solvents which are inert to the reactants.

Examples of such solvents or diluents are water, aliphatic, alicyclic and aromatic hydrocarbons, that can optionally be chlorinated, such as for example hexane, cyclohexane, petroleum ether, ligroin, benzene, toluene, xylene, methylene chloride, chloroform, carbon tetrachloride, ethylene dichloride and trichloroethane, ethers, such as for example diisopropyl ether, dibutyl ether, propylene oxide, dioxane and tetrahydrofuran, ketones, such as for example acetone, methyl ethyl ketone, methyl isopropyl ketone and methyl isobutyl ketone, nitriles, such as for example acetonitrile and propionitrile, alcohols, such as for example methanol, ethanol, isopropanol, butanol and ethylene glycol, esters, such as for example ethyl acetate and amyl acetate, amides, such as for example dimethylformamide and dimethylacetamide, sulphones and sulphoxides, such as for example dimethyl sulphoxide and sulpholane, and bases, such as for example pyridine.

The reaction is suitably carried out between room temperature and the boiling point of the particular reaction mixture. The reaction can be carried out under atmospheric pressure but if desired higher or lower pressures can be used.

Process variant (A) is preferably carried out in chlorinated hydrocarbons, such as dichloromethane or dichloroethane, in the presence of a catalyst and/or acid acceptor. Examples of these are tertiary amines, such as for example triethylamine, diisopropylethylamine, N-methylmorpholine, 4-dimethylaminopyridine and pyridine. Pyridine can be used both as catalyst and as a solvent.

Process variant (B) is preferably carried out in inert solvents, such as dioxane, tetrahydrofuran, dimethylformamide or N-methylpyrrolidone, optionally in the presence of a catalyst. Examples of these are metal hydrides, tertiary amines, such as for example triethylamine or diisopropylethylamine and inorganic bases, such as for example alkali metal or alkaline earth metal hydroxides or carbonates.

The compounds of the invention prepared by these processes can be isolated from the reaction mixtures in conventional manner, for example by distillation of the solvent at normal or reduced pressure, by precipitation with water or by extraction.

A higher level of purity can be achieved as a rule by column chromatography as well as by fractionated distillation or crystallisation.

The compounds of the invention are, as a rule, colourless or odourless crystals that are slightly soluble in water and in aliphatic hydrocarbons, such as petroleum ether, hexane, pentane and cyclohexane, and highly soluble in halogenated hydrocarbons, such as chloroform, methylene chloride and carbon tetrachloride, aromatic hydrocarbons, such as benzene, toluene and xylene, ethers, such as diethyl ether, tetrahydrofuran and dioxane, nitriles, such as acetonitrile, alcohols, such as methanol and ethanol, amides, such as dimethylformamide, and sulphoxides, such as dimethyl sulphoxide.

The compounds of formula II, III, IV and V can be prepared as described in the literature and especially as described in EP Application 0 246 749.

As stated previously the compounds of the invention show good herbicidal activity. This activity is seen against monocotyledonous and dicotyledonous weeds with good selectivity in various crops as well as in sugar beet.

The compounds of the invention can be used for example against the following plant species:

Dicotyledonous weeds of the species Sinapis, Lepidium, Galium, Stellaria, Matricaria, Anthemis, Galinsoga, Chenopodium, Brassica, Urtica, Senecio, Amaranthus, Portulaca, Xanthium, Convolvulus, Ipomoea, Polygonum, Sesbania, Ambrosia, Cirsium, Carduus, Sonchus, Solanum, Rorippa, Lamium, Veronica, Abutilon, Datura, Viola, Galeopsis, Papaver, Centaurea and Chrysanthemum.

Monocotyledonous weeds of the species Avena, Alopecurus, Echinochloa, Setaria, Panicum, Digitaria, Poa, Eleusine, Brachiaria, Lolium, Bromus, Cyperus, Agropyron, Sagittaria, Monocharia, Fimbristylis, Eleocharis, Ischaemum and Apera.

The rates of use vary depending on the manner of pre- and postemergent use between 0.01 and 5 kg/ha.

The compounds of the invention can be used either alone or in admixture with one another or with other active agents. Optionally, other plant-protective agents or pesticides can be added, depending on the purpose for the treatment. When it is desired to broaden the spectrum of activity, other herbicides can also be added.

Herbicidally active mixing partners suitable in this connection include for example, the active agents listed in Weed Abstracts, Vol. 36, No. 12 (1987) under the heading "List of common names and abbreviations employed for currently used herbicides and plant growth regulators in Weed Abstracts".

An improvement in the intensity and speed of action can be obtained, for example, by addition of suitable adjuvants, such as organic solvents, wetting agents and oils. Such additives may allow a decrease in the dose.

The designated active ingredients or their mixtures can suitable be used, for example, as powders, dusts, granules, solutions, emulsios or suspensions, with the addition of liquid and/or solid carriers and/or diluents and, optionally, binding, wetting, emulsifying and/or dispersing adjuvants.

Suitable liquid carriers are, for example aliphatic and aromatic hydrocarbons, such as benzene, toluene, xylene, cyclohexanone, isophorone, dimethyl sulphoxide, dimethylformamide and other mineral-oil fractions and plant oils.

Suitable solid carriers include mineral earths, e.g. bentonite, silica gel, talcum, kaolin, attapulgite, limestone, silicic acid and plant products, e.g. flours.

As surface-active agents there can be used for example calcium lignosulphonate, polyoxyethylenealkylphenyl ether, naphthalenesulphonic acids and their salts, phenolsulphonic acids and their salts, formaldehyde condensates, fatty alcohol sulphates, as well as substituted benzenesulphonic acids and their salts.

The percentage of the active ingredient(s) in the various preparations can vary within wide limits. For example the compositions can contain about 10 to 90 percent by weight active ingredients, and about 90 to 10 percent by weight liquid or solid carriers, as well as, optionally up to 20 percent by weight of surfactant.

The agents can be applied in customary fashion, for example with water as the carrier in spray mixture volumes of approximately 100 to 1,000 l/ha. The agents can be applied using low-volume or ultra-low-volume techniques or in the form of so-called microgranules.

The preparation of these formulations can be carried out in known manner, for example by milling or mixing processes. Optionally, individual components can be mixed just before use for example by the so-called commonly used tank-mixing method.

Formulations can be prepared, for example, from the following ingredients.

(A)

Wettable Powder (1)

25 percent by weight active ingredient

60 percent by weight kaolin

10 percent by weight silicic acid

5 percent by weight of a mixture of calcium ligninsulphonate and the sodium salt of N-methyl-N-oleyltaurine

(2)

40 percent by weight active ingredient

25 percent by weight clay minerals

25 percent by weight silicic acid

10 percent by weight of a mixture of calcium lignosulphonate and alkylphenyl polyglycol ether

(B)

Paste

45 percent by weight active ingredient

5 percent by weight sodium aluminium silicate

15 percent by weight cetyl polyglycol ether with 8 mol of ethylene oxide

2 percent by weight spindle oil

10 percent by weight polyethylene glycol

23 percent by weight water

(C)

Emulsifiable Concentrate

25 percent by weight active ingredient

15 percent by weight cyclohexanone

55 percent by weight xylene

5 percent by weight of a mixture of calcium dodecylbenzenesulphonate and nonylphenolpolyoxyethylene.

The following examples illustrate the preparation of compounds according to the invention.

EXAMPLE 1 N-(2-Difluoromethoxy-6-methylphenyl)-1-(4-chloro-6-methoxypyrimidin-2-yl)-1H-1,2,4-triazole-3-sulphonamide

1.8 g (6 mmol) N-(2-Difluoromethoxy-6-methylphenyl)-1H-1,2,4-triazole-3-sulphonamide in 10 ml dimethylformamide was stirred with 1.68 g (12 mmol) potassium carbonate for 10 minutes at 50° C. It was then cooled to 10° C. and treated with 1.33 g (6 mmol) 4-chloro-6-methoxy-2-methylsulphonylpyrimidine and the mixture stirred for 45 minutes at 10° C. It was then added to ice-water, acidified to pH 4 with sulphuric acid and the solid collected and purified by silica gel chromatography using a mixture of methylene chloride and methanol (95/5).

Yield: 1.1 g=41% of theory.

M.p.: 215°-216° C.

In a similar manner to these processes the following compounds were prepared.

    __________________________________________________________________________     Example                                                                             Name of Compound       Physical Constant                                  __________________________________________________________________________      2   N-(2,6-Difluorophenyl)-1-(4-chloro-6-                                                                 mp: 229-234° C.                                  methoxypyrimidin-2-yl)-1H-1,2,4-triazole-                                      3-sulphonamide                                                             3   N-(2,6-Dichlorophenyl)-1-(4-chloro-6-                                                                 mp: 235-240° C.                                  methoxypyrimidin-2-yl)-1H-1,2,4-triazole-                                      3-sulphonamide                                                             4   N-(2-Methoxycarbonyl-6-methylphenyl)-                                                                 mp: 147-152° C.                                  1-(4-chloro-6-methoxypyrimidin-2-yl)-1H-                                       1,2,4-triazole-3-sulphonamide                                              5   N-(2,6-Dichloro-3-methylphenyl)-1-(4-                                                                 mp: 217-221° C.                                  chloro-6-methoxypyrimidin-2-yl)-1H-                                            1,2,4-triazole-3-sulphonamide                                              6   N-(2-Chloro-6-methylphenyl)-1-(4-                                                                     mp: 228-233° C.                                  chloro-6-methoxypyrimidin-2-yl)-1H-                                            1,2,4-triazole-3-sulphonamide                                              7   N-(2,6-Dichloro-3-methylphenyl)-1-(4-                                                                 mp: 212-215° C.                                  chloro-6-ethoxypyrimidin-2-yl)-1H-                                             1,2,4-triazole-3-sulphonamide                                              8   N-(2-Trifluoromethylphenyl)-1-(4-                                                                     mp: 191-194° C.                                  chloro-6-methoxypyrimidin-2-yl)-1H-                                            1,2,4-triazole-3-sulphonamide                                              9   N-(2-Methoxyphenyl)-1-(4-chloro-                                                                      mp: 175-178° C.                                  6-methoxypyrimidin-2-yl)-1H-                                                   1,2,4-triazole-3-sulphonamide                                             10   N-(2-Methoxycarbonyl-6-methyphenyl)-1-                                                                mp: 142-148° C.                                  (4-chloro-6-ethoxypyrimidin-2-yl)-1H-                                          1,2,4-triazole-3-sulphonamide                                             11   N-(2-Methyl-6-nitrophenyl)-1-(4-                                                                      mp: 221-224° C.                                  chloro-6-methoxypyrimidin-2-yl)-1H-                                            1,2,4-triazole-3-sulphonamide                                             12   N-(2,6-Dichlorophenyl)-1-(4-                                                                          mp: 251-259° C.                                  chloro-6-ethoxypyrimidin-2-yl)-1H-                                             1,2,4-triazole-1-sulphonamide                                             13   N-(2,6-Difluorophenyl)-1-(4-                                                                          mp: 190-193° C.                                  chloro-6-ethoxypyrimidin-2-yl)-1H-                                             1,2,4-triazole-3-sulphonamide                                             14   N-(2,3-Dimethyl-6-nitrophenyl)-1-(4-                                                                  mp: 226-230° C.                                  chloro-6-methoxypyrimidin-2-yl)-1H-                                            1,2,4-triazole-3-sulphonamide                                             15   N-(2-Difluoromethoxy-6-methylphenyl)-                                                                 mp: 147-150° C.                                  1-(4-chloro-6-ethoxypyrimidin-2-yl)-1H-                                        1,2,4-triazole-3-sulphonamide                                             16   N-(2-Difluoromethoxyphenyl)-1-(4-                                                                     mp: 178-181° C.                                  chloro-6-methoxypyrimidin-2-yl)-1H-                                            1,2,4-triazole-3-sulphonamide                                             17   N-(2-Difluoromethoxyphenyl)-1-(4-                                                                     mp: 157-161° C.                                  chloro-6-ethoxypyrimidin-2-yl)-1H-                                             1,2,4-triazole-3-sulphonamide                                             18   N-(2,6-Dibromophenyl)-1-(4-                                                                           mp: 266° C. (decomp)                             chloro-6-methoxypyrimidin-2-yl)-1H-                                            1,2,4-triazole-3-sulphonamide                                             19   N-(2-Allyloxy-6-nitrophenyl)-1-(4-                                                                    mp: 173-176° C.                                  chloro-6-methoxypyrimidin-2-yl)-1H-                                            1,2,4-triazole-3-sulphonamide                                             20   N-(2-Methoxy-6-nitrophenyl)-1-(4-                                                                     mp: 222-225° C.                                  chloro-6-methoxypyrimidin-2-yl)-1H-                                            1,2,4-triazole-3-sulphonamide                                             21   N-(2-Propargyloxy-6-nitrophenyl)-1-(4-                                                                mp: 176-180° C.                                  chloro-6-methoxypyrimidin-2-yl)-1H-                                            1,2,4-triazole-3-sulphonamide                                             22   N-(2-Methoxy-6-nitrophenyl)-1-(4-                                                                     mp: 230-232° C.                                  chloro-6-ethoxypyrimidin-2-yl)-1H-                                             1,2,4-triazole-3-sulphonamide                                             23   N-(2-Allyloxy-6-nitrophenyl)-1-(4-                                                                    mp: 132-135° C.                                  chloro-6-ethoxypyrimidin-2-yl)-1H-                                             1,2,4-triazole-3-sulphonamide                                             24   N-(2-Propargyloxy-6-nitrophenyl)-1-(4-                                                                mp: 192-196° C.                                  chloro-6-methoxypyrimidin-2-yl)-1H-                                            1,2,4-triazole-3-sulphonamide                                             25   N-(2,6-Dichloro-1-methylphenyl)-1-(4-                                                                 mp: 197-199° C.                                  chloro-6-n-propoxypyrimidin-2-yl)-1H-                                          1,2,4-triazole-3-sulphonamide                                             26   N-(2-Difluormethoxy-6-methylphenyl)-                                           1-(4-chloro-6 -n-propoxypyrimidin-2-yl)-                                       1H-1,2,4-triazole-1-sulphonamide                                          27   N-(2-Allyloxy-6-nitrophenyl)-1-(4-                                                                    mp: 164° C.                                      chloro-6-n-propoxypyrimidin-2-yl)-1H-                                          1,2,4-triazole-3-sulphonamide                                             28   N-(2,6-Difluorophenyl)-1-(4-chloro-                                            6-n-propoxypyrimidin-2-yl)-1H-                                                 1,2,4-triazole-3-sulphonamide                                             29   N-(2-Methoxycarbonyl-6-methylphenyl)-1-                                        (4-chloro-6-n-propoxypyrimidin-2-yl)-1H-                                       1,2,4-triazole-3-sulphonamide                                             30   N-(2-Methoxy-6-methoxycarbonylphenyl)-1-                                                              mp: 166-167° C.                                  (4-chloro-6-n-propoxypyrimidin-2-yl)-1H-                                       1,2,4-triazole-3-sulphonamide                                             31   N-(2,6-Dichloro-3-methylphenyl)-1-(4-                                                                 mp: 187° C.                                      chloro-6-isopropoxypyrimidin-2-yl)-1H-                                         1,2,4-triazole-3-sulphonamide                                             32   N-(2-Difluoromethoxy-6-methylphenyl)-1-                                        (4-chloro-6-isopropoxypyrimidin-2-yl)-1H-                                      1,2,4-triazole-3-sulphonamide                                             33   N-(2-Allyloxy-6-nitrophenyl)-1-(4-chloro-                                                             mp: 171-172° C.                                  6-isopropoxypyrimidin-2-yl)-1H-1,2,4-                                          triazole-3-sulphonamide                                                   34   N-(2,6-Difluorophenyl)-1-(4-chloro-                                            6-isopropoxypyrimidin-2-yl)-1H-1,2,4-                                          triazole-3-sulphonamide                                                   35   N-(2-Methoxycarbonyl-6-methylphenyl)-1-(4-                                     chloro-6-isopropoxypyrimidin-2-yl)-1H-                                         1,2,4-triazole-3-sulphonamide                                             36   N-(2-Methoxy-6-methoxycarbonylphenyl)-1-(4-                                                           mp: 179-180° C.                                  chloro-6-isopropoxypyrimidin-2-yl)-1H-                                         1,2,4-triazole-3-sulphonamide                                             37   N-(2-Methoxycarbonyl-4-methyl-3-thienyl)-                                      1-(4-chloro-6-methoxypyrimidin-2-yl)-1H-                                       1,2,4-triazole-3-sulphonamide                                             38   N-(2-Methoxycarbonyl-4-methyl-3-thienyl)-                                      1-(4-chloro-6-ethoxypyrimidin-2-y1)-1H-                                        1,2,4-triazole-3-sulphonamide                                             39   N-(2-Methoxy-6-methoxycarbonylphenyl)-                                                                mp: 174-176° C.                                  1-(4-chloro-6-methoxypyrimidin-2-yl)-1H-                                       1,2,4-triazole-3-sulphonamide                                             40   N-(2,6-Difluorophenyl)-1-(4-chloro-                                                                   mp: 183-185° C.                                  6-methoxypyrimidin-2-yl)-5-methyl-1H-                                          1,2,4-triazole-3-sulphonamide                                             41   N-(2,6-Dichlorophenyl)-1-(4-chloro-6-                                                                 mp: 224-225° C.                                  methoxypyrimidin-2-yl)-5-methyl-1H-                                            1,2,4-triazole-3-sulphonamide                                             42   N-(2,6-Dichloro-3-methylphenyl)-1-(4-                                                                 mp: 214-215° C.                                  chloro-6-methoxypyrimidin-2-yl)-5-                                             methyl-1H-1,2,4-triazole-3-sulphonamide                                   43   N-(2-Methyl-6-nitrophenyl)-1-(4-                                                                      mp: 209-210° C.                                  chloro-6-methoxypyrimidin-2-yl)-5-                                             methyl-1H-1,2,4-triazole-3-sulphonamide                                   44   N-(2,6-Difluorophenyl)-1-(4-chloro-                                                                   mp: 185-186° C.                                  6-methoxypyrimidin-2-yl)-5-methoxy-                                            methyl-1H-1,2,4-triazole-3-sulphonamide                                   45   N-(2,6-Dichlorophenyl)-1-(4-chloro-                                                                   mp: 193-195° C.                                  6-methoxypyrimidin-2-yl)-5-methoxy-                                            methyl-1H-1,2,4-triazole-3-sulphonamide                                   46   N-(2-Difluoromethoxy-6-methylphenyl)-1-                                                               mp: 201-204° C.                                  (4-chloro-6-methoxypyrimidin-2-yl)-5-                                          methyl-1H-1,2,4-triazole-3-sulphonamide                                   47   N-(2-Methoxycarbonyl-6-methylphenyl)-1-                                                               mp: 162-165° C.                                  (4-chloro-6-methoxypyrimidin-2-yl)-5-                                          methyl-1H-1,2,4-triazole-3-sulphonamide                                   48   N-(2-Methoxycarbonyl-4-methyl-3-thienyl)-                                                             mp: 162-165° C.                                  1-(4-chloro-6-methoxypyrimidin-2-yl)-5-                                        methyl-1H-1,2,4-triazole-3-sulphonamide                                   49   N-(2-Chloro-6-methoxycarbonylphenyl)-1-                                                               mp: 191-193° C.                                  (4-chloro-6-methoxypyrimidin-2-yl)-5-                                          methyl-1H-1,2,4-triazole-3-sulphonamide                                   50   N-(2-Difluoromethoxy-6-methylphenyl)-1-                                                               mp: 134-136° C.                                  (4-chloro-6-methoxypyrimidin-2-yl)-5-                                          methoxymethyl-1H-1,2,4-triazole-3-sulphonamide                            51   N-(2-Methoxycarbonyl-4-methyl-3-thienyl)-                                                             mp: 181-183° C.                                  1-(4-chloro-6-methoxypyrimidin-2-yl)-5-                                        methoxymethyl-1H-1,2,4-triazole-3-sulphonamide                            52   N-(2-Methoxy-6-methoxycarbonylphenyl)-1-                                                              mp: 212-213° C.                                  (4-chloro-6-methoxypyrimidin-2-yl)-5-                                          methyl-1H-1,2,4-triazole-3-sulphonamide                                   __________________________________________________________________________

The following examples illustrate the possibilities for use of the compounds of the invention.

EXAMPLE A

In a greenhouse, the noted plant species were treated pre-emergently with the noted compounds, at a rate of 0.03 kg active ingredient/ha. The compounds were sprayed evenly over the plants as emulsions in 500 liters water/ha. Three weeks after the treatment, the compounds of the invention showed a high crop selectivity in wheat as well as in typical succeeding cultures as sugar beets and rape with excellent activity against the weeds. The comparison materials did not show the similar high selectivity.

In the following table:

0=no damage

4=total destruction

-=not tested

TRZAX=Triticum aestivum

BEAVS=Beta vulgaris

BRSSS=Brassica sp.

MATCH=Matricaria chamomilla.

    ______________________________________                                         Compounds of                                                                   invention    TRAZAX   BEAVX    BRSSS  MATCH                                    ______________________________________                                         Example 2    0        0        1      4                                        Example 5    0        0        1      4                                        Example 8    0        0        0      4                                        Example 9    0        0        0      4                                        Example 10   0        0        0      4                                        Example 11   0        1        0      4                                        Example 16   0        0        1      4                                        Example 17   0        0        0      4                                        Example 18   0        0        0      4                                        Example 19   0        0        0      4                                        Example 20   0        1        3      4                                        Example 21   0        1        2      4                                        Example 22   0        0        --     3                                        Example 23   0        0        --     3                                        Example 24   0        1        --     3                                        Untreated    0        0        0      0                                        Comparison                                                                     Thiameturon-methyl                                                                          0        3        3      4                                        Compound I 30                                                                               --       3        --     4                                        from EP Application                                                            0 246 749                                                                      Compound I 36                                                                               --       4        --     4                                        from EP Application                                                            0 246 749                                                                      ______________________________________                                    

EXAMPLE B

In a greenhouse, the noted plant species were treated post-emergently with the noted compounds, at a rate of 0.03 kg active ingredient/ha. The compounds were sprayed evenly over the plants as emulsions in 500 liters water/ha. Two weeks after the treatment, the compounds of the invention showed a high crop selectivity in wheat as well as in typical succeeding cultures as sugar beets and rape as well as in cotton with excellent activity against the weeds. The comparison material did not show the similar high selectivity.

In the following table:

0=no damage

4=total destruction

-=not tested

TRZAX=Triticum aestivum

BEAVS=Beta vulgaris

BRSSS=Brassica sp.

GOSHI=Gossypium hirsutum

MATCH=Matricaria chamomilla.

    __________________________________________________________________________     Compounds of                                                                   invention TRZAX BEAVX                                                                               BRSSS                                                                               GOSHI                                                                               MATCH                                           __________________________________________________________________________     Example 2 0     0    1    0    3                                               Example 3 0     1    1    0    3                                               Example 4 0     1    0    1    3                                               Example 5 0     0    0    0    3                                               Example 6 0     1    1    0    4                                               Example 7 0     0    0    0    3                                               Example 8 0     0    0    0    4                                               Example 10                                                                               0     0    0    0    3                                               Example 11                                                                               0     0    0    0    4                                               Example 15                                                                               0     0    --   0    4                                               Example 16                                                                               0     0    1    0    4                                               Example 20                                                                               0     1    3    0    3                                               Example 21                                                                               0     0    2    0    3                                               Example 22                                                                               0     0    --   0    3                                               Example 23                                                                               0     0    --   0    3                                               Example 24                                                                               0     0    --   0    3                                               Untreated 0     0    0    0    0                                               Comparison                                                                     Thiameturon-methyl                                                                       0     4    4    3    4                                               __________________________________________________________________________

EXAMPLE C

In a greenhouse, the compounds of the invention were sprayed pre-emergently over pots with Matricaria of different origin and with sugar beet varieties. The amount of water corresponded to about 200 liters/ha. In the following table the plant growth, four weeks after the treatment, is given as a relative value of the fresh weight of the plants compared with untreated plants.

As the example shows the compounds of the invention are well compatible to sugar beets and have at the same time an excellent activity against camomile.

In the following table:

MATCH=Matricaria chamomilla

BEAVA=Beta vulgaris ssp. vulgaris var. altissima

BEAVC=Beta vulgaris ssp. vulgaris var. crassa

    ______________________________________                                                 Dose     Fresh weight                                                  Compounds                                                                              g active (relative to untreated)                                               Dose                                                                   Compounds                                                                              g active                                                               of      ingredi-          MATCH                                                invention                                                                              ent/ha   MATCH    (UK)   BEAVA  BEAVC                                  ______________________________________                                         Example 3                                                                               3       9        6      98     98                                             10       0        0      104    99                                     Example 5                                                                              10       6        2      96     97                                             30       0        0      101    95                                     Example 8                                                                              10       0        0      99     99                                             30       0        0      93     97                                             100      0        0      98     192                                    Example 19                                                                             30       0        0      104    97                                             100      0        0      99     99                                     Example 20                                                                             10       0        0      100    103                                    Example 21                                                                             10       0        0      110    106                                            30       0        0      94     92                                     Example 22                                                                             10       0        0      98     --                                             30       0        0      97     --                                     Example 23                                                                             10       1        1      69     104                                            30       0        0      100    107                                    Example 24                                                                             10       0        0      94     107                                            30       0        0      93     110                                    Untreated                                                                              --       100      100    100    100                                    Comparison                                                                     Ethofumesate                                                                           500      107      78     89     96                                             1000     88       82     74     100                                    ______________________________________                                    

EXAMPLE D

In a greenhouse, the compounds of the invention were sprayed post-emergently over pots with plants of Matricaria species and sugar beet varieties. The amount of water corresponded to about 200 liters/ha. Two weeks after the treatment, the fresh weight of the plants was dertermined and given in the following table as a relative value compared with untreated plants.

As the example shows the compounds of the invention are well compatible to sugar beets and have at the same time an excellent activity against camomile. The comparison material did not show the similar high activity.

In the following table:

MATCH=Matricaria chamomilla

MATIN=Matricaria inodora

MATMT=Matricaria matricarioides

BEAVA=Beta vulgaris ssp. vulgaris var. altissima

BEAVC=Beta vulgaris ssp. vulgaris var. crassa

BEAVD=Beta vulgaris ssp. vulgaris var. conditiva.

    __________________________________________________________________________                    Fresh weight                                                            Dose   (relative to untreated)                                         Compounds of                                                                           g active    MATCH                                                      invention                                                                              ingredient/ha                                                                         MATCH                                                                               (UK) MATIN                                                                               MATMT                                                                               BEAVA                                                                               BEAVC                                                                               BEAVD                             __________________________________________________________________________     Example 3                                                                              300    4    7    19    3   93   91   85                                Example 4                                                                              100    6    7    21   18   98   95   86                                        300    3    5     9    7   95   95   81                                Example 5                                                                              300    12   13   54   26   106  99   90                                Example 6                                                                              300    6    6     8   14   95   94   99                                Example 8                                                                              100    6    11   48   13   107  103  98                                Example 22                                                                             300    8    4    13    7   91   95   98                                Example 23                                                                             300    9    10   20   12   95   96   95                                Example 24                                                                             300    8    9    16   12   99   96   110                               Untreated                                                                              --     100  100  100  100  100  100  100                               Comparison                                                                     Phenmedipham                                                                           320    46   49   50   26   104  130  105                                       960    18   23   20   12   98   93   90                                __________________________________________________________________________

EXAMPLE E

In a greenhouse, the noted plant species were treated pre-emergently with the noted compounds of the invention, at the rate shown. The compounds of the invention were sprayed evenly over the vessels containing seeds of the plants as an aqueous acetone solution containing a wetting agent. After 3 to 4 weeks growth, the plants were visually assessed for any herbicidal response.

In the following table:

0=no effect

1=1-24% effect

2=35-69% effect

3=70-89% effect

4=90-100% effect

-=not tested

GALAP=Galium aparine

MATIN=Matricaria inodora

MATCH=Matricaria chamomila

BEAVS=Beta vulgaris.

    __________________________________________________________________________     Compounds of                                                                           kg active                                                              invention                                                                              ingredient/ha                                                                         GALAP MATIN                                                                               MATCH                                                                               BEAVS                                           __________________________________________________________________________     Example 40                                                                              0.032 3     4    --   0                                               Example 41                                                                             0.25   3     --   --   2                                               Example 42                                                                              0.016 1     4    4    0                                               Example 43                                                                             0.25   3     --   --   2                                               Example 44                                                                             0.25   2     --   --   2                                               Example 45                                                                             0.25   3     --   --   2                                               Example 46                                                                             0.25   3     --   --   2                                               Example 47                                                                              0.016 3     4    4    0                                               Example 48                                                                             0.25   2     4    2    1                                               Example 49                                                                              0.016 2     4    4    1                                               Example 50                                                                              0.016 --    4    4    1                                               Example 51                                                                              0.032 2     4    --   2                                               Example 52                                                                             0.25   4     --   --   --                                              Untreated                                                                              --     0     0    0    0                                               __________________________________________________________________________

EXAMPLE F

In a greenhouse, seedlings of the noted plant species were treated post-emergently with the noted compounds of the invention, at the rate shown. The compounds of the invention were sprayed evenly over the vessels containing the plants as an aqueous acetone solution containing a wetting agent. After 3 to 4 weeks growth, the plants were visually assessed for any herbicidal response.

In the following table:

0=no effect

1=1-24% effect

2=25-69% effect

3=70-89% effect

4=90-100% effect

-=not tested

GALAP=Galium aparine

MATIN=Matricaria inodora

MATCH=Matricaria chamomila

BEAVS=Beta vulgaris.

    __________________________________________________________________________     Compounds of                                                                           kg active                                                              invention                                                                              ingredient/ha                                                                         GALAP MATIN                                                                               MATCH                                                                               BEAVS                                           __________________________________________________________________________     Example 40                                                                             0.016  3     4    4    2                                               Example 41                                                                             0.25   4     --   --   2                                               Example 42                                                                             0.125  3     --   --   1                                               Example 43                                                                             0.25   2     --   --   2                                               Example 44                                                                             0.25   2     --   --   2                                               Example 45                                                                             0.016  2     4    4    0                                               Example 46                                                                             0.25   4     3    3    2                                               Example 47                                                                             0.25   3     --   --   --                                              Example 49                                                                             0.125  4     --   --   2                                               Example 50                                                                             0.125  4     4    --   2                                               Example 52                                                                             0.125  4     4    --   2                                               Untreated                                                                              --     0     0    0    0                                               __________________________________________________________________________ 

We claim:
 1. 1-Chloropyrimidinyl-1H-1,2,4-triazole-3-sulphonamide of formula I ##STR9## in which A is --S-- or --CH═CH--;R¹ is halogen, methyl, trifluoromethyl, methoxy, difluoromethoxy, nitro or methoxycarbonyl; R² is hydrogen, halogen, methyl, methoxy, allyloxy or propargyloxy; R³ is hydrogen or methyl; R⁴ is hydrogen, methyl or methoxymethyl; and R⁵ is C₁ -C₄ -alkyl.
 2. A herbicidal composition which comprises a herbidically effective amount of a compound according to claim 1, in admixture with agriculturally acceptable carriers or diluents.
 3. A method of combating weeds which comprises applying to the weeds or their locus a herbicidally effective amount of a compound according to claim
 1. 4. A sulphonamide according to claim 1 in whichA is --CH═CH--; R¹ is halogen, difluormethoxy or methoxycarbonyl, R² is halogen or methyl, R³ is hydrogen or methyl, R⁴ is hydrogen and R⁵ is methyl.
 5. A sulphonamide according to claim 4 in which R¹ is halogen.
 6. A sulphonamide according to claim 4 in which R¹ is difluormethoxy.
 7. A sulphonamide according to claim 4 in which R¹ is methoxycarbonyl.
 8. The sulphonamide of claim 4 in which R² is halogen.
 9. The sulphonamide of claim 4 in which R² is methyl.
 10. The sulphonamide of claim 4 in which R³ is halogen.
 11. The sulphonamide of claim 4 in which R³ is methyl.
 12. N-(2,6-Dichloro-3-methylphenyl)-1-(4-chloro-6-methoxypyrimidin-2-yl)-1H-1,2,4-triazole-3-sulphonamide according to claim
 2. 13. A herbicidal composition which comprises a herbidically effective amount of a compound according to claim 12, in admixture with agriculturally acceptable carriers or diluents.
 14. A herbicidal composition which comprises a herbidically effective amount of a compound according to claim 4, in admixture with agriculturally acceptable carriers or diluents.
 15. A method of combating weeds which comprises applying to the weeds or their locus a herbicidally effective amount of a compound according to claim
 12. 16. A method of combating weeds which comprises applying to the weeds or their locus a herbicidally effective amount of a compound according to claim
 4. 